Swan Goose

Anser cygnoides

The Swan Goose is the largest goose. It has a natural breeding
range in Mongolia, northernmost China, and southeastern Russia.
It is migratory and winters mainly in central and eastern China.
It is listed as endangered in the wild, but the species has been
domesticated, and extensively kept as poultry. A domestic Swan
Goose usually has a large knob at the base of the bill (the wild
form lacks this). It is notable for its long, swanlike beak and
neck. The Swan Goose feeds almost exclusively on plants,
including sedges. It often grazes on dry land. Farmers sometimes
make use of the domesticated form of the bird for weeding their
crops. Theyve also been raised for their eggs.